Typically, machines such as servers owned by a plurality of companies at a data center, for example, are mounted on server racks and installed collectively in a machine room because of space limitations, air conditioning conditions, and other reasons. A worker mostly works on the machines from the outside through a network, but works physically at places where the machines are located when, for example, replacing or adding a component. In this case, once the worker has entered the machine room to perform the work, for example, at the data center, the worker has access to machines of other companies in the machine room, which is a security problem.
In a known technique to maintain the security in the machine room, for example, at the data center, the server racks on which the machines are mounted are housed in a cage, for example, so as to physically prevent entry thereto. In another known technique, the machine room is divided into an area in which the worker is allowed to stay and a prohibited area in which the worker is not allowed to stay, so that position information of the worker can be managed and the existence of the worker in the prohibited area can be detected.
Patent Literature 1: Japanese Laid-open Patent Publication No. 2011-214844
Patent Literature 2: Japanese Laid-open Patent Publication No. 02-154357
Patent Literature 3: Japanese Laid-open Patent Publication No. 05-35407
Patent Literature 4: Japanese Laid-open Patent Publication No. 2013-149905
However, in the above techniques, the security can be maintained but with an adverse effect. For example, the server racks housed in the cage or the like prevent effective use of their installation areas and also hinder change of arrangement in the machine room. On the other hand, the technique of managing the position information of the worker can effectively use space in the machine room as compared to the method of physically dividing an area with a cage or the like, but needs extremely high installation cost.